China has called on Washington to “stop the unreasonable crackdown” on Huawei after the US stepped up pressure on the tech giant by indicting it on charges of stealing technology and violating sanctions on Iran.

Beijing will “firmly defend” its companies, a foreign ministry statement said.

It gave no indication whether Beijing might retaliate for the charges against Huawei, China’s first global tech brand and the biggest maker of switching gear for phone and Internet companies.